/**
 * @(#)HttpUtils.java 2/04/2009
 *
 * Copyright (c) 2005-2010 PsiqueWare S.A. de C.V. All Rights Reserved.
 * This software is the proprietary information PsiqueWare S.A. de C.V.
 * Use is subject to license terms.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND ANY EXPRESS OR
 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND
 * FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR
 * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER
 * IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
 * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 *
 *
 * <br/>Usuario : AngelElectrico
 * <br/>Creaci&oacute;n: 2/04/2009 - 01:01:04 PM
 * <br/>
 * <br/>
 * <br/><t5>Cambios :</t5>
 * <br/><b>Fecha | Autor  |  Cambios</b>
 * <ul>
 * <li>2/04/2009 | <a href = "mailto:AngelElectrico@PsiqueWare.com">Angel El&eacute;ctrico</a> | Creaci&oacute;n del Objeto.</li>
 *
 * </ul>
 */

package com.psiqueware.alheli.basico.util;

import java.io.BufferedInputStream;
import java.io.BufferedOutputStream;
import java.io.File;
import java.io.FileNotFoundException;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.net.URI;
import java.net.URL;
import java.net.URLConnection;

/**
 * Utilidades de HTTP.
 * <br/>Paquete Original: com.psiqueware.orquidea.gui.util
 * <br/>Nombre  Original: HttpUtils
 * <br/>Oprima para ver : <a href="HttpUtils.java.html"><i>C&oacute;digo Fuente</i> </a>
 *
 * @author <a href="mailto:AngelElectrico@PsiqueWare.com">Angel El&eacute;ctrico</a>
 * @version Revision: 1.1 2/04/2009 01:01:04 PM
 * @noinspection UnusedDeclaration
 */
public final class WebUtil
{

    /**
     * Interfase para un escucha para los eventos de la descarga por Http.
     */
    public static interface EscuchaDescarga
    {

        /**
         * Invocado cuando ya se han realizado las conexiones y se va a iniciar la descarga.
         */
        void inicioDescarga();

        /**
         * Invocado para reportar el n&uacute;mero de bytes descargados.
         *
         * @param bytes descargados.
         */
        void bytesDescargados(final long bytes);

        /**
         * Invocado en caso de que se produzca una excepci&oacute;n.
         *
         * @param e producida. En general puede ser un {@link FileNotFoundException} o un {@link IOException}.
         */
        void error(final Exception e);

        /**
         * Invocado cuando se ha terminado de realizar la descarga.
         */
        void finalizaDescarga();
    }

    /**
     * Descarga un recurso remoto en un archivo local.
     *
     * @param uriRecurso    {@link URL} al recurso a descargar.
     * @param archivoSalida {@link File} donde se escribir&aacute; el archivo.
     * @param escucha       {@link EscuchaDescarga} para los eventos de descarga. Pueder ser <code>null</code>.
     *
     * @return <code>true</code> si se realiz&oacute; correctamente la descarga; <code>false</code> en caso contrario.
     */
    public static boolean descargar(final URI uriRecurso, final File archivoSalida, final EscuchaDescarga escucha)
    {
        boolean salida = false;
        OutputStream out = null;
        URLConnection conn;
        InputStream in = null;
        try
        {
            long descargados = 0;
            out = new BufferedOutputStream(new FileOutputStream(archivoSalida));
            conn = uriRecurso.toURL().openConnection();
            in = conn.getInputStream();
            if (null != escucha) escucha.inicioDescarga();
            byte[] buffer = new byte[1024];
            int numRead;
            while ((numRead = in.read(buffer)) != -1)
            {
                out.write(buffer, 0, numRead);
                buffer = new byte[1024];
                if (null != escucha)
                {
                    descargados += 1024;
                    escucha.bytesDescargados(descargados);
                }
            }
            if (null != escucha) escucha.finalizaDescarga();
            salida = true;
        }
        catch (FileNotFoundException e)
        {
            if (null != escucha) escucha.error(e);
        }
        catch (IOException e)
        {
            if (null != escucha) escucha.error(e);

        }
        catch (final Exception exception)
        {
            if (null != escucha) escucha.error(exception);
        }
        finally
        {
            if (in != null)
            {
                try
                {
                    in.close();
                }
                catch (IOException ioe)
                {
                    ioe.printStackTrace();
                }
            }
            if (out != null)
            {
                try
                {
                    out.close();
                }
                catch (IOException ioe)
                {
                    ioe.printStackTrace();
                }
            }
        }
        return salida;
    }


    /**
     * Descarga un recurso remoto en un archivo local utilizando buffers.
     *
     * @param urlRecurso    {@link URL} al recurso a descargar.
     * @param archivoSalida {@link File} donde se escribir&aacute; el archivo.
     * @param escucha       {@link EscuchaDescarga} para los eventos de descarga. Pueder ser <code>null</code>.
     *
     * @return <code>true</code> si se realiz&oacute; correctamente la descarga; <code>false</code> en caso contrario.
     */
    public static boolean descargarConBuffer(final URL urlRecurso, final File archivoSalida, final EscuchaDescarga escucha)
    {
        boolean salida = false;
        BufferedInputStream in = null;
        BufferedOutputStream out = null;
        try
        {
            URLConnection urlc = urlRecurso.openConnection();
            in = new BufferedInputStream(urlc.getInputStream());
            out = new BufferedOutputStream(new FileOutputStream(archivoSalida));
            if (null != escucha) escucha.inicioDescarga();

            long bytes = 0;
            int i;
            while ((i = in.read()) != -1)
            {
                out.write(i);
                if (null != escucha) escucha.bytesDescargados(++bytes);
            }
            if (null != escucha) escucha.finalizaDescarga();
            salida = true;
        }
        catch (IOException e)
        {
            if (null != escucha) escucha.error(e);
        }
        catch (final Exception exception)
        {
            if (null != escucha) escucha.error(exception);
        }
        finally
        {
            if (in != null)
            {
                try
                {
                    in.close();
                }
                catch (IOException ioe)
                {
                    ioe.printStackTrace();
                }
            }
            if (out != null)
            {
                try
                {
                    out.close();
                }
                catch (IOException ioe)
                {
                    ioe.printStackTrace();
                }
            }
        }
        return salida;
    }

    /**
     * Conversiones hexadecimales.
     */
    private final static String[] hex = {
            "%00", "%01", "%02", "%03", "%04", "%05", "%06", "%07",
            "%08", "%09", "%0a", "%0b", "%0c", "%0d", "%0e", "%0f",
            "%10", "%11", "%12", "%13", "%14", "%15", "%16", "%17",
            "%18", "%19", "%1a", "%1b", "%1c", "%1d", "%1e", "%1f",
            "%20", "%21", "%22", "%23", "%24", "%25", "%26", "%27",
            "%28", "%29", "%2a", "%2b", "%2c", "%2d", "%2e", "%2f",
            "%30", "%31", "%32", "%33", "%34", "%35", "%36", "%37",
            "%38", "%39", "%3a", "%3b", "%3c", "%3d", "%3e", "%3f",
            "%40", "%41", "%42", "%43", "%44", "%45", "%46", "%47",
            "%48", "%49", "%4a", "%4b", "%4c", "%4d", "%4e", "%4f",
            "%50", "%51", "%52", "%53", "%54", "%55", "%56", "%57",
            "%58", "%59", "%5a", "%5b", "%5c", "%5d", "%5e", "%5f",
            "%60", "%61", "%62", "%63", "%64", "%65", "%66", "%67",
            "%68", "%69", "%6a", "%6b", "%6c", "%6d", "%6e", "%6f",
            "%70", "%71", "%72", "%73", "%74", "%75", "%76", "%77",
            "%78", "%79", "%7a", "%7b", "%7c", "%7d", "%7e", "%7f",
            "%80", "%81", "%82", "%83", "%84", "%85", "%86", "%87",
            "%88", "%89", "%8a", "%8b", "%8c", "%8d", "%8e", "%8f",
            "%90", "%91", "%92", "%93", "%94", "%95", "%96", "%97",
            "%98", "%99", "%9a", "%9b", "%9c", "%9d", "%9e", "%9f",
            "%a0", "%a1", "%a2", "%a3", "%a4", "%a5", "%a6", "%a7",
            "%a8", "%a9", "%aa", "%ab", "%ac", "%ad", "%ae", "%af",
            "%b0", "%b1", "%b2", "%b3", "%b4", "%b5", "%b6", "%b7",
            "%b8", "%b9", "%ba", "%bb", "%bc", "%bd", "%be", "%bf",
            "%c0", "%c1", "%c2", "%c3", "%c4", "%c5", "%c6", "%c7",
            "%c8", "%c9", "%ca", "%cb", "%cc", "%cd", "%ce", "%cf",
            "%d0", "%d1", "%d2", "%d3", "%d4", "%d5", "%d6", "%d7",
            "%d8", "%d9", "%da", "%db", "%dc", "%dd", "%de", "%df",
            "%e0", "%e1", "%e2", "%e3", "%e4", "%e5", "%e6", "%e7",
            "%e8", "%e9", "%ea", "%eb", "%ec", "%ed", "%ee", "%ef",
            "%f0", "%f1", "%f2", "%f3", "%f4", "%f5", "%f6", "%f7",
            "%f8", "%f9", "%fa", "%fb", "%fc", "%fd", "%fe", "%ff"
    };

    /**
     * Encode a string to the "x-www-form-urlencoded" form, enhanced
     * with the UTF-8-in-URL proposal. This is what happens:
     * <p/>
     * <ul>
     * <li><p>The ASCII characters 'a' through 'z', 'A' through 'Z',
     * and '0' through '9' remain the same.
     * <p/>
     * <li><p>The unreserved characters - _ . ! ~ * ' ( ) remain the same.
     * <p/>
     * <li><p>The space character ' ' is converted into a plus sign '+'.
     * <p/>
     * <li><p>All other ASCII characters are converted into the
     * 3-character string "%xy", where xy is
     * the two-digit hexadecimal representation of the character
     * code
     * <p/>
     * <li><p>All non-ASCII characters are encoded in two steps: first
     * to a sequence of 2 or 3 bytes, using the UTF-8 algorithm;
     * secondly each of these bytes is encoded as "%xx".
     * </ul>
     *
     * @param strUtf8 The string to be encoded
     *
     * @return The encoded string
     */
    public static String encodeUTF8ToUrl(String strUtf8)
    {
        StringBuffer sbuf = new StringBuffer();
        int len = strUtf8.length();
        for (int i = 0; i < len; i++)
        {
            int ch = strUtf8.charAt(i);
            if ('A' <= ch && ch <= 'Z')
            {        // 'A'..'Z'
                sbuf.append((char) ch);
            }
            else if ('a' <= ch && ch <= 'z')
            {    // 'a'..'z'
                sbuf.append((char) ch);
            }
            else if ('0' <= ch && ch <= '9')
            {    // '0'..'9'
                sbuf.append((char) ch);
            }
            else if (ch == ' ')
            {            // space
                sbuf.append('+');
            }
            else if (ch == '-' || ch == '_'        // unreserved
                    || ch == '.' || ch == '!'
                    || ch == '~' || ch == '*'
                    || ch == '\'' || ch == '('
                    || ch == ')')
            {
                sbuf.append((char) ch);
            }
            else if (ch <= 0x007f)
            {        // other ASCII
                sbuf.append(hex[ch]);
            }
            else if (ch <= 0x07FF)
            {        // non-ASCII <= 0x7FF
                sbuf.append(hex[0xc0 | (ch >> 6)]);
                sbuf.append(hex[0x80 | (ch & 0x3F)]);
            }
            else
            {                    // 0x7FF < ch <= 0xFFFF
                sbuf.append(hex[0xe0 | (ch >> 12)]);
                sbuf.append(hex[0x80 | ((ch >> 6) & 0x3F)]);
                sbuf.append(hex[0x80 | (ch & 0x3F)]);
            }
        }
        return sbuf.toString();
    }
}

